Laptop, nouveau and external monitor

[H]

On January 1, 2025 9:51:30 PM EST, H <agents at meddatainc.com> wrote:
>Running the latest version of Rocky Linux 9 fully updated and Mate on a
>Dell Inspiron 7570 laptop with a UHD display, i.e. 3840 x 2160 pixels.
>I would like to attach two external monitors and initially experimented
>with a Dell dock model 3100 and the latest version of the DisplayLink
>and evdi drivers. However, although the Mate display applet shows the
>correct resolution for the laptop display itself and for the external
>monitor which is running at 1920 x 1080 pixels, the resolution on the
>second, external display is more like 640 x 480 pixels.
>
>While I initially thought this was due to a bug in the DisplayLink/evdi
>drivers, I see the same issue when I connect the monitor directly to
>the HDMI output on the laptop itself, ie. DisplayLink/evdi are
>presumably not involved although they are installed, nor is the dock of
>course.
>
>I just discovered running xrandr --listmonitors that, while the
>internal laptop monitor is labeled eDP-1, xrandr identifies the
>external monitor as using DP-1 although it uses the laptop
>HDMI-connector. Further, while mate hardware display monitor also
>identifies it as using DP-1 - possibly based on xrandr output - the
>monitor itself tells me it is connected using its HDMI1 connector.
>xrandr does report the correct display resolution, though.
>
>Thus, it looks like xrandr/nouveau misreads the configuration feeding
>it to mate. I just updated the laptop BIOS to the very latest version
>and saw no difference.
>
>I am using an HDMI-HDMI cable with no adapters. I have tried both
>booting with the external monitor already attached and
>attaching/reattaching it later. The monitor is an Acer S230HL monitor.
>
>I am using the nouveau driver and inxi reports the presence of both
>Intel UHD Graphics 620 and Nvidia GM108M (GeForce 940MX).
>
>The kernel is:
>Linux 5.14.0-503.15.1.el9_5.x86_64 #1 SMP PREEMPT_DYNAMIC Tue Nov 26
>17:24:29 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
>
>Could this be an nouveau bug (I am running X11 and not Wayland)? How
>should I troubleshoot it?
>
>Appreciate ideas!

The problem could lie with x or with the video driver, the latter reporting to X. According to X.org.log I am running X Server 1.20.11.

One of my concerns is why X reports that DP-1 connection is used with the external monitor whereas it in reality uses HDMI without any adapters. That suggests something is reported incorrectly which could conceivably lead to some other problem.

I am attaching X.org.log which to me seems to suggest that it is using the noveau driver. Note that I just tried to disconnect/reconnect the external monitor but could not find any log of that connection towards the end of the log
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